Formation of A2B2 supramolecular porphyrinco-polymers

Abstract

New supramolecular A₂B₂ co-polymers formed in solution from a rigid diporphyrin monomer (the A₂ unit) and a short flexible dipyridine monomer (the B₂ unit) are reported; NMR experiments show that complete binding occurs at mM concentrations; UV titrations reveal that the dipyridine unit and a monomeric control ligand have identical binding constants, confirming that linear polymers were generated (in preference to small cyclic oligomers); at 2 × 10⁻² M polymers with an average molecular weight of 17 100 g mol⁻¹ and containing approximately 14 porphyrin units have formed.